1607: With 350m to go, Armstrong is narrowly ahead of Basso - but Basso makes his move, takes the lead and secures the stage victory.

1606: With crowds lining the street cheering the riders, Armstrong and Basso are wheel-to-wheel as the finish looms.

1602: Sastre has been caught and Armstrong and Basso are having an incredible battle to take the stage.

1559: Armstrong makes a break and is giving it everything on the last climb, trying to put as much distance between himself and his rivals as possible. But CSC rider Ivan Basso is sitting on the American's shoulder.

1554: Team CSC rider Carlos Sastre makes an attack and pulls away from the small leading group. There are less than 5km left to race.

1552: Five-times winner Armstrong is stamping his authority on the stage and is in a superb position to close the gap on the overall classification leader Voeckler.

1549: Rasmussen is caught and Armstrong eases past, leading the US Postal team to the front. The 1997 Tour winner Ullich is falling behind and looks to be in trouble.

1547: The US Postal team are setting a fast pace and Hamilton and Ullrich are struggling to keep up.

1545: Rasmussen is now over half a minute ahead of the peloton, which includes Armstrong, Mayo, Ullrich and Hamilton.

1535: The peloton reforms as the small lead group is caught, but Rasmussen remains 15 seconds ahead, followed by Virenque and then David Etxebarria.

1530: The descent has split the peloton and a small lead group has formed - among them are Arnstrong and Ullrich. Ahead of them, by 10 seconds, are Rasmussen and Virenque.

1520: Rabobank's Michael Rasmussen leads the peloton by a few seconds, but the US Postal team are biding their time and taking it in turns to push the pace. Lance Armstrong is well-placed, while Jan Ullrich is on his shoulder.

1511: Moreau and Virenque drop back to the peloton and shortly after, Simeoni is reeled in too.

1508: Christophe Moreau breaks from the peloton and catches Simeoni, and the pair are quickly joined by Richard Virenque.

1506: Domina Vacanze rider Filippo Simeoni launches an attack on the peloton, which is headed by the US Postal team.

1500: The peloton catches the group of four escapees at the 157km mark and the all the riders are now together on the slopes of the Col d'Aspin.

1440: The leading group of four riders reaches the 150km mark, but their advantage over the peloton is rapidly reducing and now stands at just over a minute.

1437: Yellow jersey wearer Thomas Voeckler drops to the back of the peloton to swap bikes, which may be designed to help the Frenchman cope with the increasingly testing conditions.

1435: The peloton is coping well with the difficult conditions and has signifcantly closed the gap on the four escapees.

1430: It is now raining on the riders, with the sky very grey and overcast, and the wet roads will prove an additional challenge.

1415: The average speed for the third hour is just under 40km per hour, while the pace in the first two hours was 42.6kmh. The average speed is likely to continue to drop as bad weather awaits the riders.

It is raining heavily at the stage 12 finish - storms had been forecast and that prediction looks as though it will be accurate.

1400: The peloton has picked up the pace and reduced the gap to the four leaders to less than three minutes.

1345: The US Postal team continues to head the peloton, but the four escapees still have a considerable advantage - the gap is three minutes and 50 seconds.

1330: Pre-stage favourite Iban Mayo is forced to drop to the back of the peloton and change his bike.

Mikel Pradera of the Illes Balears team has abandoned the race - he was in 152nd place overall.

1325: The four leaders have 95km left to race and are three minutes and 55 seconds ahead of the peloton.

1315: After more than two hours of racing, the riders approach the category one climb Col d'Aspin.

1300: It is the third time La Mongie has hosted a Tour stage finish and the last time, in 2002, five-times champion Lance Armstrong led the field home.

1245: The US Postal and Brioches la Boulangere teams are leading the peloton, but there is no sign that the main bunch is attemtping to catch the four escapees, who have 125km left to race.

1230: The four escapees now have a lead of four minutes and 20 seconds and the peloton appears to be unconcerned.

One member of the main bunch, Baden Cooke, has other worries - the 2003 green jersey winner has a puncture in his rear tyre.

1210: Frenchman Nicolas Portal looked to have made a surge in pursuit of the four escapees, but it was soon clear he had simply rode ahead of the peloton to make a stop and say hello to his family.

He quickly rejoins the bunch, which is now three minutes and 55 seconds adrift of the leaders.

1200: The leading group are now two minutes and 40 seconds ahead of the peloton, as the pace is once again impressive despite a road-level temperature of 43 degrees Celsius.

Yellow jersey wearer Thomas Voeckler seems to be suffering, though, and has dropped to the back of the peloton to consult the race doctor.

1150: Despite a series of further attacks on the peloton, the bunch remain together but the gap to the four escapees has increased to one minute and 50 seconds after 35km of racing.

1140: The four escapees are pushing each other on and have now opened up a gap of one minute and 15 seconds between themselves and the peloton.

CSC rider Jens Voigt is giving chasing and has made up 15 seconds on the breakaway group.